Kudos to my mother on this one, one that I understand now but still don't quite live up to.
I always asked my mother when I would be considered a man. My father didn't live with us and as the only male in the family I felt that I should be the man of the house.
Whenever I asked, however, I got told simply
"A man is a boy who has stopped trying to prove he's a man"
Now I get it, I understand the difference between the child-hood want to be somewhere that you aren't and the adult acceptance of who and where you are. Like I said, I don't always live up to it but it always gives me comfort when I take the time to think on it.